In the past, various systems and devices have been employed to contain fluids escaping from ruptures in fluid hoses. Fluid hoses, which are typically composed of rubber, tend to wear and break down with time. This deterioration is exacerbated by bending of the hose and the repeated flow of fluid through the hose. Hot water hoses, which are commonly used with household appliances, are particularly susceptible to wear because of the stresses caused by repeated changes in the temperature thereof. As the hose deteriorates, the likelihood of a rupture increases. In the event that the hose ruptures, leaks, or bursts, significant flooding and serious water damage can result. Similarly, ruptures in hydraulic hoses can result in oil burns, fire burns and other injuries associated with the sudden release of hot fluid. Moreover, if the rupture occurs in a hydraulic hose utilized in a boat, or other watercraft, the rupture can result in a major water pollution event. In addition, the rupture of a hydraulic hose or conduit in an aircraft flight control system can have devastating effects due to the loss of control of the aircraft.
In the past, double-wall hoses have been used to contain leaking fluids. Double-wall hoses include an inner hose which is surrounded by an outer hose where, in the event that the inner hose ruptures, the outer hose contains the leaking fluid. Often, the outer hose is connected to a drain and the leaking fluid is directed away from the rupture. However, drains are not always located nearby and, as a result, these devices have limitations. In one application, outer sleeves are placed on the hot and cold water hoses of a clothes washing machine and a drainage hose is interconnected between the outer sleeves to conduct water from a leaking inner hose to a standard drain line. Assembling the outer hoses to the inner hoses is complicated, time-consuming, and often impractical. Furthermore, these systems merely control the fluid flowing from the rupture; however, they do not provide any means for stopping the flow of fluid through the inner hose after it has ruptured.
In the past, electronic sensors have been positioned in the outer hose of double-wall hoses to detect fluid leaking from the inner hose. These sensors are placed in communication with a CPU, or microprocessor, which shuts off the supply of fluid to the inner hose by closing a valve upstream from the rupture. These devices are invariably expensive and are typically difficult for most homeowners to install. Further, not only does the electronic circuitry add cost and reduce the reliability of the system, it also requires the presence of electrical power to function. If a water leak occurs coincidentally with an electrical power outage, the valve may fail to accomplish its purpose unless auxiliary power is supplied.
Other types of systems are known in the art. For example, a soluble-link valve has been used to stop the flow of fluid through a hose. The soluble-link valve includes a valve member, a spring which acts to place the valve member in a closed position, and a fluid-soluble link which holds the valve member in an open position. In use, escaped fluid dissolves the fluid-soluble link holding the valve member in the open position and, thereafter, the spring moves the valve member from the open position into the closed position. However, while the soluble-link is dissolving, fluid may continue to flow through the rupture and damage the surrounding structure and/or environment.
Recent devices include a flood control hose assembly that responds to catastrophic hose ruptures. These devices include a moveable valve member, a valve seat, and a spring positioned within the hose which biases the valve member into an open position. In use, fluid flowing through the hose applies a force to the valve member. Under typical operating conditions, this force is sufficient to compress the spring, but it is not sufficient to seat the valve member against the valve seat. When a rupture occurs in the hose, the pressure differential across the valve may increase and the fluid flowing through the valve may flow faster. As a result, the force applied to the valve member may increase and seat the valve member against the valve seat. However, this type of valve is typically unable to respond to minor leaks or ruptures in the hose. More particularly, minor leaks from the hose may not cause sufficient fluctuations in the fluid flow to actuate the valve. As a result, this type of valve can usually only respond to excessively large changes in fluid flow such as those witnessed during a catastrophic rupture. Clearly, these devices have limitations and an improvement is needed over the foregoing.